1. Field of the Invention
The present invention relates to sharpeners, and in particular, to motor driven sharpeners for soft pencils.
2. Description of Related Art
Cosmetic pencils and artists' pencils employ a relatively soft core. These pencils must be frequently sharpened when in use. For example, a cosmetologist may need to sharpen a pencil ten or more times during a single session with a customer.
Sharpeners for soft pencils are typically manual. Such sharpeners employ a frame having a conical cavity. The conical cavity has a slit that is partially covered by a blade. A pencil is sharpened by rotating the frame and its blade around the point of a pencil. Manual devices for sharpening cosmetic pencils are shown in U.S. Pat. Nos. 3,097,629; 4,248,283; 4,402,354; and 5,167,071.
Known motor driven sharpeners employ conical barrels with splined exteriors. These sharpening cones grind the pencil point. Such grinding is inappropriate for a soft element pencil such as a cosmetic or artist's pencil, because the grinding produces a roughened, unusable surface.
For a motor driven blade to work satisfactorily with a soft element pencil, the blade must be open, exposed and relatively free from obstructions. If the motor driven blade is mounted on a frame adjacent a slot of a conical cavity, the soft core shavings will quickly clog the slot.
The sharpener in U.S. Pat. No. 3,059,617 has a blade holder that is spun by an electric motor. The blade in this reference is shut in and relatively obstructed. Thus this blade holder will tend to clog when sharpening soft pencils. See also U.S. Pat. Nos. 1,887,843; 3,175,539, and 4,050,487.
Various other pencil sharpeners are shown in U.S. Pat. Nos. 715,849; 1,121,423; 2,626,593; 3,090,358; 3,115,869; 3,659,637; and 4,231,405.
Accordingly, there is a need for an improved sharpener for a soft element pencil such as a cosmetic or artist's pencil that operates efficiently and without clogging or grinding.